diff --git a/src/ProtocolBuffers/EnumLite.cs b/src/ProtocolBuffers/EnumLite.cs
index 527a29d81a..4234483582 100644
--- a/src/ProtocolBuffers/EnumLite.cs
+++ b/src/ProtocolBuffers/EnumLite.cs
@@ -93,11 +93,11 @@ namespace Google.ProtocolBuffers
             }
         }
 
-        private readonly Dictionary<int, IEnumLite> items;
+        private readonly SortedList<int, IEnumLite> items;
 
         public EnumLiteMap()
         {
-            items = new Dictionary<int, IEnumLite>();
+            items = new SortedList<int, IEnumLite>();
 #if SILVERLIGHT2
     // Silverlight doesn't support Enum.GetValues
     // TODO(jonskeet): Validate that this reflection is permitted, e.g. in Windows Phone 7
diff --git a/src/ProtocolBuffers/FieldSet.cs b/src/ProtocolBuffers/FieldSet.cs
index 2769977154..f3c08cf57e 100644
--- a/src/ProtocolBuffers/FieldSet.cs
+++ b/src/ProtocolBuffers/FieldSet.cs
@@ -87,12 +87,8 @@ namespace Google.ProtocolBuffers
 
         public static FieldSet CreateInstance()
         {
-#if SILVERLIGHT2
-            return new FieldSet(new Dictionary<IFieldDescriptorLite, object>());
-#else
             // Use SortedList to keep fields in the canonical order
             return new FieldSet(new SortedList<IFieldDescriptorLite, object>());
-#endif
         }
 
         /// <summary>
@@ -313,16 +309,7 @@ namespace Google.ProtocolBuffers
         /// </summary>
         internal IEnumerator<KeyValuePair<IFieldDescriptorLite, object>> GetEnumerator()
         {
-#if SILVERLIGHT2
-            List<KeyValuePair<IFieldDescriptorLite, object>> result = new List<KeyValuePair<IFieldDescriptorLite, object>>(fields);
-            result.Sort(
-                delegate(KeyValuePair<IFieldDescriptorLite, object> a, KeyValuePair<IFieldDescriptorLite, object> b)
-                { return a.Key.CompareTo(b.Key); }
-            );
-            return result.GetEnumerator();
-#else
             return fields.GetEnumerator();
-#endif
         }
 
         /// <summary>
@@ -474,12 +461,9 @@ namespace Google.ProtocolBuffers
         /// </summary>
         public void WriteTo(ICodedOutputStream output)
         {
-            using (IEnumerator<KeyValuePair<IFieldDescriptorLite, object>> e = GetEnumerator())
+            foreach (KeyValuePair<IFieldDescriptorLite, object> entry in fields)
             {
-                while (e.MoveNext())
-                {
-                    WriteField(e.Current.Key, e.Current.Value, output);
-                }
+                WriteField(entry.Key, entry.Value, output);
             }
         }
 
diff --git a/src/ProtocolBuffers/ProtocolBuffersLite.csproj b/src/ProtocolBuffers/ProtocolBuffersLite.csproj
index 66edab75c7..bc58bf1145 100644
--- a/src/ProtocolBuffers/ProtocolBuffersLite.csproj
+++ b/src/ProtocolBuffers/ProtocolBuffersLite.csproj
@@ -110,6 +110,7 @@
       <SubType>Code</SubType>
     </Compile>
     <Compile Include="InvalidProtocolBufferException.cs" />
+    <Compile Include="SortedList.cs" />
     <Compile Include="ThrowHelper.cs" />
     <Compile Include="UninitializedMessageException.cs" />
     <Compile Include="WireFormat.cs" />